Image MIME Reference
Corel-CMX
Corel Metafile Exchange
image/x-cmx
VS
JPEG 2000 Part 2 (Extended)
image/jpx
JPX
A complete technical comparison of Corel Metafile Exchange and JPEG 2000 Part 2 (Extended) — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | Corel-CMX | JPX |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | ✕ No | Yes |
| Progressive Loading | ✕ No | Yes |
| HDR Support | ✕ No | Yes |
| EXIF Metadata | ✕ No | Yes |
| ICC Color Profile | Yes | Yes |
Corel Metafile Exchange
image/x-cmx
Extension
.cmx
Container
RIFF (Resource Interchange File Format)
Compression
Uncompressed Vector Commands / Embedded Raster Compression (Optional)
Algorithm
None (Vector)
Color Depth
Vector Data, Supports embedded bitmaps
Developed by
Corel Corporation
Released
Mid-1990s
Magic Bytes
52 49 46 46 (skip 4) 43 4D 58 31
JPEG 2000 Part 2 (Extended)
image/jpx
Extension
.jpx.jpf
Container
ISOBMFF / JPX (ISO/IEC 15444-2)
Compression
Lossy / Lossless
Algorithm
Discrete Wavelet Transform (DWT)
Color Depth
8-bit, 16-bit, 32-bit, 38-bit
Developed by
Joint Photographic Experts Group (JPEG)
Released
2002
Magic Bytes
00 00 00 0C 6A 50 20 20 0D 0A 87 0A ... 66 74 79 70 6A 70 78 20
Browser Support Comparison
| Browser | Corel-CMX | JPX |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
Corel-CMX
Corel-CMX Strengths
- Preserves rich vector attributes and layer groupings native to the Corel drawing engine better than standard WMF files
- Significantly smaller footprint than full CDR project files, making it excellent for early CD-ROM clip art distribution
- Maintains decent support in the open-source community thanks to libraries like libcdr
Limitations
- Proprietary format strictly tied to Corel's ecosystem, often causing compatibility issues with Adobe software
- Zero support in web browsers; must be converted to SVG for modern web usage
- Largely obsolete for modern workflows, superseded by PDF and SVG
JPX
JPX Strengths
- Removes the color space limitations of baseline JP2, adding native support for CMYK, CIE Lab, and custom vendor color spaces
- Supports multiple codestreams in a single file, allowing for rich compositing and animation
- Enables fragmented files where image data and metadata can reside in separate physical files via data references
Limitations
- Extremely complex specification makes full software implementation rare, leading to compatibility issues
- Zero web browser support, rendering it unsuitable for public internet distribution
- Often overkill for standard imaging tasks where baseline JP2 or modern alternatives like AVIF suffice
When to choose which format
Corel-CMX
Use Corel-CMX when…
- Legacy CorelDRAW Clip Art Collections
- Vector Graphic Exchange within Corel Suite
- Historical Desktop Publishing Assets
JPX
Use JPX when…
- Prepress & Commercial Printing (CMYK)
- Geospatial Data
- Archival Preservation
- Medical Imaging